1. Field of the Invention
The invention relates to an apparatus for transporting documents and, more particularly, to an apparatus for buffering transport of documents between a document input at a first rate and a document output at a second different rate.
2. Brief Description of Prior Developments
In some document handling systems, such as an inserter, for example, used for inserting documents into envelopes, buffering of collations is an essential process in order to achieve optimum system throughput. In many cases the buffer machine utilizes rollers, clutches, and brakes. Such machines are limited to small collation sizes (such as less than 15 documents, for example, in a stack or collation), and also tend to introduce skew in the documents of a stack. Operators often adjust nip pressure and introduce straps and side guides to correct for this problem.
In addition, these machines often drive the collation with one axis and spring load the other axis in order to create a driving nip. This introduces undesired “shingling” to the collation, and this problem becomes worse for larger height collations or stacks.